This invention relates generally to printers for computers, and more particularly to such printers that are mobile in nature.
Mobile computers, commonly called notebook or laptop computers, have become increasingly popular. Whereas desktop computers force their users to work at only a single location, laptop computers allow their users greater freedom in where the users can work. Users can, for instance, bring their laptop computers home from work and back again, and can also work on them in airplanes, trains, and otherwise while traveling.
As notebook computers have become more powerful, approaching that of their desktop counterparts, users have begun to expect the same peripherals that they use with their desktop computers. For example, many notebook computers come equipped with DVD, CD-ROM, and other types of drives, enabling their users to play movies and install software off optical media no different than if they were using desktop computers. With the advent of wireless networking, both wireless wide-area networking (WAN) and wireless local-area networking (LAN), users can even access network resources across broad areas when using their laptop computers.
One common peripheral that users enjoy having access to is the printer, which enables them to print hardcopies of documents that they may be working on with their laptop computers. Mobile printers, however, have not advanced to the same degree as laptop computers have. Although mobile printers are frequently smaller than their non-mobile counterparts, they are still overly complex, bulky, orientation sensitive, and power hungry. Their added weight means that users may think twice before bringing them along on a trip. Their general inability to run for extended periods off battery power means that users may not be able to use them as conveniently as they can their laptop computers.
In many instances, mobile printers do not represent a rethinking of how a printer functions, but rather only a miniaturization of the innards of a more conventional printer. A common printing technology used in mobile printers is inkjet technology. An inkjet printer is a printer that places extremely small droplets of ink onto paper to create an image. Other types of printers include dot matrix printers, laser printers, and printers that use solid ink, dye sublimation, thermal wax, and thermal autochrome technologies. However, inkjet technology is most popular for mobile printing applications, perhaps because of its relatively low cost, ability to print in different colors, and ability to have its components miniaturized, among other reasons.
A typical inkjet printer, be it a desktop or a mobile printer, usually has a number of common components, regardless of its brand, speed, and so on. There is a print head that contains a series of nozzles used to spray drops of ink onto paper. Ink cartridges, either integrated into the print head or separate therefrom, supply the ink. There may be separate black and color cartridges, color and black in a single cartridge, or cartridges for each ink color. A print head stepper motor typically moves the print head assembly back and forth horizontally, or laterally, across the paper, where a belt is used to attach the assembly to the motor. The assembly may use a stabilizer bar to ensure that print head movement is precise and controlled. Rollers pull paper from a tray, feeder, or the user""s manual input, and advance the paper to new vertical locations on the paper.
The significant difference in existing mobile inkjet printers from desktop inkjet printers, then, is in the size of their components, which allows the mobile printers to be more transportable. The print head may be smaller, which enables a smaller and less powerful motor to be used to horizontally move the print head across the paper. There may not be a dedicated tray or paper feeder to supply paper to the print head, the printer instead relying on the user to feed the paper to the rollers to push or pull through the printer. The vast majority of mobile printers still rely on rollers to allow the printer to print on different vertically oriented regions of the paper, with the print head itself moving horizontally to print on different horizontally oriented regions of the paper.
However, the paper-feed mechanism of printers in general likely prevents this miniaturization from continuing to the point where an optimal mobile printer is designed. Merely decreasing the size of printer components to essentially turn a desktop printer into a mobile printer likely does not result in a mobile printer that is as small, lightweight, and able to run off batteries as it could be. For these and other reasons, therefore, there is a need for the present invention.
In one embodiment, a portable printer includes a top cover, a bottom cover, one or more rail units located on the inside surface of the top cover, and a carriage assembly. Media is positionable on the inside surface of the bottom cover. The carriage assembly is movably connected to the rail units, such that the carriage assembly is able to move at least one of horizontally and vertically over the media, and print on substantially any part of the media, wherein the media is capable of being stationary during printing.
Still other embodiments, aspects, and of the invention will become apparent by reading the detailed description that follows, and by referring to the accompanying drawings.